From: Borislav Petkov <bp@xxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit c6a385539175ebc603da53aafb7753d39089f32e upstream. So Sebastian turned off the PIE for kernel builds but that was too late - Kbuild.include already uses KBUILD_CFLAGS and trying to disable gcc options with, say cc-disable-warning, fails: gcc -D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs ... -Wno-sign-compare -fno-asynchronous-unwind-tables -Wframe-address -c -x c /dev/null -o .31392.tmp /dev/null:1:0: error: code model kernel does not support PIC mode because that returns an error and we can't disable the warning. For example in this case: KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,) which leads to gcc issuing all those warnings again. So let's turn off PIE/PIC at the earliest possible moment, when we declare KBUILD_CFLAGS so that cc-disable-warning picks it up too. Also, we need the $(call cc-option ...) because -fno-PIE is supported since gcc v3.4 and our lowest supported gcc version is 3.2 right now. Signed-off-by: Borislav Petkov <bp@xxxxxxx> Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx> Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Michal Marek <mmarek@xxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- Makefile | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/Makefile b/Makefile index 7b106de05fef..e001c1c9e0a4 100644 --- a/Makefile +++ b/Makefile @@ -378,11 +378,12 @@ KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ -Werror-implicit-function-declaration \ -Wno-format-security \ -fno-delete-null-pointer-checks \ - -std=gnu89 + -std=gnu89 $(call cc-option,-fno-PIE) + KBUILD_AFLAGS_KERNEL := KBUILD_CFLAGS_KERNEL := -KBUILD_AFLAGS := -D__ASSEMBLY__ +KBUILD_AFLAGS := -D__ASSEMBLY__ $(call cc-option,-fno-PIE) KBUILD_AFLAGS_MODULE := -DMODULE KBUILD_CFLAGS_MODULE := -DMODULE KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds @@ -583,8 +584,6 @@ endif # $(dot-config) all: vmlinux KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,) -KBUILD_CFLAGS += $(call cc-option,-fno-PIE) -KBUILD_AFLAGS += $(call cc-option,-fno-PIE) ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE KBUILD_CFLAGS += -Os -- 2.10.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html